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Thousands of wolf spiders crawled out of the soil and covered the ground in silk during a flood. (Daniel Munoz / Reuters)

Field of Cobwebs

An article about spiders that covered an area in silk after a flood

A million spiders can live in an acre of field. (Daniel Munoz / Reuters)

Are you afraid of spiders? If so, what happened in Australia might be your worst nightmare. This past March, flooding drove thousands of wolf spiders from their underground homes. Once above ground, the spiders blanketed farmlands around the town of Wagga Wagga with silk.

A million spiders can live in an acre of field, says Owen Seeman, an arachnologist who studies spiders at the Queensland Museum in Australia. But, he says, “unless you get down on your hands and knees and stick your nose in the grass, you won’t notice they’re there.”

To flee the rising waters, the spiders crawled out of hiding and tried to “fly” to safety by ballooning. That’s when a spider climbs to a high point, like the end of a blade of grass, and then tips its abdomen toward the sky and releases silk into the wind like a kite string. If a strong enough gust catches the unspooling silk, it lifts the spider into the air and carries it off to a new location. Spiders can fly up to 100 kilometers (62 miles) this way!

It can take spiders multiple attempts to lift off. After every failed launch, the spider’s silk drops, creating a thick blanket over everything on the ground. Seeman says the wind in Wagga Wagga wasn’t strong enough to pick up many spiders. Most of them probably survived and crawled back down when the water receded.

Wolf spiders aren’t dangerous to people. So coming across a field of ballooning ones shouldn’t scare you. With thousands of spiders flying through the air, though, you might want to keep your mouth closed.